The revolving drum of a winch used to haul lines is called a（）.

The purpose for the bag or box on top of some survival craft is to（）.

A.right the craft in case of capsizing
B.increase area for radar detection
C.act as a sail in case of a power loss
D.steady the craft in heavy seas

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The locking pin that joins the parts of a detachable link is held in position by（）.

A.a tack weld
B.the self-locking characteristics of its taper
C.a cotter pin
D.a lead plug

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